Bacteroides fragilis (B. fragilis) is a Gram-negative anaerobe and an integral component of the gut microflora of most mammals. Although members of the genus Bacteroides are numerically the most abundant intestinal organisms, B. fragilis itself represents only a very small fraction of the fecal flora in humans Although a minor component of the flora, B. fragilis is the most commonly isolated organism from clinical cases of intra-abdominal abscess. B. fragilis can produce at least eight structurally distinct capsular polysaccharides (denoted as polysaccharides A-H), of which polysaccharide A (PSA) is the most abundantly expressed.
There is a need for treating subjects with viral infection associated inflammation. Provided herein are compositions including PSA and methods of treating viral infection and viral infection associated inflammation with compositions including PSA.